Electric Resistance of Elastic Strain Sensors—Fundamental Mechanisms and Experimental Validation

Abstract

Elastic strain sensor nanocomposites are emerging materials of high scientific and commercial interest. This study analyzes the major factors influencing the electrical behavior of elastic strain sensor nanocomposites. The sensor mechanisms were described for nanocomposites with conductive nanofillers, either dispersed inside the polymer matrix or coated onto the polymer surface. The purely geometrical contributions to the change in resistance were also assessed. The theoretical predictions indicated that maximum Gauge values are achieved for mixture composites with filler fractions slightly above the electrical percolation threshold, especially for nanocomposites with a very rapid conductivity increase around the threshold. PDMS/CB and PDMS/CNT mixture nanocomposites with 0–5.5 vol.% fillers were therefore manufactured and analyzed with resistivity measurements. In agreement with the predictions, the PDMS/CB with 2.0 vol.% CB gave very high Gauge values of around 20,000. The findings in this study will thus facilitate the development of highly optimized conductive polymer composites for strain sensor applications.

Long‐term application of core spun fabric strain sensor manufactured via dip coating for large deformation monitoring

“…Strain sensing is a fundamental requirement in numerous fields, ranging from structural health monitoring to wearable technology applications 1–4 . A strain sensor can provide real‐time feedback on the structural health, performance, and user activities, enabling proactive maintenance, injury prevention, and performance optimization 5–10 . Traditional strain sensors, such as metallic foil or wire‐based sensors, 11,12 have limitations in terms of their flexibility, durability, and sensitivity.…”